To provide policy makers, resource managers and researchers with access to the data they need to detect, quantify, locate, understand and warn of changes (especially reductions) in the capacity of terrestrial ecosystems to support sustainable development.

Focuses on five issues of global concern:
1. Changes in land quality
2. Availability of freshwater resources
3. Loss of biodiversity
4. Impacts of climate change
5. Effect of pollution and toxicity

Food and Agriculture Organization (FAO)
International Council of Science Unions (ICSU)
United Nations Environment Programme (UNEP)
United Nations Educational, Scientific and
Cultural Organization (UNESCO)
World Meteorological Organization (WMO)

Countries (Europe, Southern Africa, South Asia)
Research institutes and universities
Global change programmes (GCOS, GOOS, IGBP ... )
Committee of earth observation satellites
Framework convention on climate change
Convention on biodiversity

1. Large-area experiments
2. Long-term research centres
3. Field stations
4. Periodic, unstaffed sample sites
5. Frequent low resolution remote sensing

GTOS
Secretariat
Steering Committee
(GTSC)
GT-Net Panel
Thematic Networks Regional / National Networks
Ecology-Net Coastal-Net Glacier-Net Hydrology-Net
Southern
Asia
Central
Europe
Southern
Africa


Arab Centre for the Studies of Arid Zones and Dry Lands (ACSAD)

Arctic Monitoring and Assessment Programme (AMAP)

Chinese Ecosystem Research Network (CERN)

Consultative Group on International Agricultural Research (CGIAR)

Fluxnet

International Cooperative Programme on Integrated Monitoring of Air Pollution Effects on Ecosystem (ICP IM)

Organismo Autonomo Parques Nationales
 Réseau d’Observatoires de Surveillance Ecologique
à Long Terme (ROSELT)

UK Environmental Change Network (ECN)

US Long-term Ecological Research Networks (LTER)

Worldwide Network of Biosphere Reserves (MAB-BR)

Objective: to link existing terrestrial monitoring networks in order to carry out studies of regional and global environmental change.
Key activities:
• to share and exchange environmental data;
• to define policies on data and information access;
• to develop standards for metadata and in situ data;
• to undertake demonstration projects
(the first one on Net Primary Productivity).

GT-Net will undertake projects which demonstrate the value of linking existing networks by generating data sets which are useful in studying global change. It will serve as a test bed for collaboration among networks and sites, including data sharing and exchange, and obtaining the experience needed for further development of GT-Net

The first project will concentrate on improving current estimates of global terrestrial primary productivity. It will adopt a hierarchical approach and use models which combine satellite data with in situ observations. A set of products, which have Net Primary Production
(NPP) as their common foundation, will be produced. The NPP project will: (1)distribute a standard global NPP product to regional networks for evaluation; and (2) derive regionally specific crop, range and forest yield maps for land management applications.

The calculation of NPP requires input data which are valuable long-term observations in their own right:
Land cover
Leaf Area Index (LAI)
Net primary productivity
Soil water holding capacity and nitrogen content
Temperature
Rainfall

Critical vegetation variables of LC,
LAI and NPP are measured at local and regional scales, and used to validate the global satellite based estimates. NEP measurements provide a separate validation and translation of the carbon budget based NPP to estimate commodity yields (with local weather data if available).

• A register of long-term terrestrial observation sites around the world
• Information on more than 700 sites
• Searchable on the Web: http://www.fao.org/gtos/
• Supporting the NPP project

• Framework to link terrestrial databases, sites, networks
• Improved access to terrestrial data & information
• Better collaboration between ecological networks
• Filling gaps in key observations
• Stronger links between science and policy
• Faster response to emerging issues
• Harmonization of measurements & terminology